Water?
What was in it, water?
About the only way for you to get anything or have anything inside your pump is through the foreward seal. This is between the impeller and pump housing, where the shaft comes through.
If you have no oil, you'll need to tear that pump down and change the seal. You'll also need to check your shaft. Most times, when you run with no oil for a short period of time, the bearings will cut a groove into the shaft. Usually, the inside (closest to the impeller) part of the shaft is the first to be etched by the bearings....
Hate to hear it but best you caught it now, before it locked up on you and tore up the pump. It could have taken out your drive shaft as well.........so, good catch.